let _ =
  let use () = 
    begin
      Printf.fprintf stderr "use : %s numcp(int) \n" Sys.argv.(0);
      flush stderr;
      exit 1
    end
  in
  if Array.length Sys.argv < 2 
  then use ()
  else
    try
      let t = int_of_string Sys.argv.(1) in
      while true do
        let line = input_line stdin in
        for i = 1 to t-1 do
          print_string line
        done;
        print_endline line
      done
    with
      | Failure _ -> use ()
      | End_of_file -> ()
